Weight Loss Support - Q:Losing Fat vs Lean Body Mass

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06-30-2008, 09:54 PM
Maybe someone here knows the answer to this question.

When losing weight, how much LBM can an active woman expect to lose, along the fat?

I know there's not a magic number, but is there a target number? Or an average?

I googled this and got zip. The reason I ask is that I've lost 7 lbs in the past month and 0.4 lbs of it was LBM. I've been strength training this past month. I wish I had the same statistics from when I was just doing cardio. I'm really curious about the effect of the lifting.

Sizewise, I've lost a total of 2" -- that includes a 1" gain in the thighs, but everything else is a bit smaller.

Just curious!

06-30-2008, 10:11 PM
Hi. Losing lean body mass is something you don't want to do. You definitly want to lose bosy fat, and the whole point of losing fat is to have bairly any left, and to have your lean body mass at your target percent...which I am not sure what yours would be, I have papers on it, so I will get back to you and let know, I know this a slack reply but I know more, so just give me a bit to find my information and I will get back to you ok!

http://www.3fatchicks.net/img/bar008/slider-scaleblue/lb/285/175/211/.png (http://www.3fatchicks.com/)

06-30-2008, 10:26 PM
Everyone loses both fat and lean body mass... the idea is to limit the loss of LBM with active exercise to keep your muscle tissue from diminishing.

Here are some body fat percentage numbers from freedieting.com:
Classification..... Women (% Fat)....... Men (% Fat)
Essential Fat...... 10-12 percent........ 2-4 percent
Athletes............ 14-20 percent........ 6-13 percent
Fitness.............. 21-24 percent....... 14-17 percent
Acceptable........ 25-31 percent........ 18-25 percent

For women, a body fat of 10-12% is essential, 14-20% is considered a healthy range for athletes, 21-24% is healthy for fitness, 25-31% is considered an 'acceptable' range and anything above 32% is considered obese.

For men, 2-4% body fat is essential, 6-13% is an athletic body fat range, 14-17% is considered a 'fit' range, and 18-25% is acceptable. Anything above 26% for men is considered obese.

Just to give you an idea, I had 44% body fat at 198. I went to 33% body fat at 155. That means that I lost more fat than LBM.

44% of 198 = 87 pounds of fat, 111 pounds LBM
33% of 155 = 51 pounds of fat, 104 pounds LBM

So, I lost about 36 pounds of fat and 7 pounds of LBM.

Lifting will help maintain or increase LBM.


06-30-2008, 11:06 PM
Ok, here is what I know, in your body you are made up of lean body mass and fat, and for me, my goal fat is 25%, I am not sure if that is for everyone, but according to my chart given to me from my dietition it never changes, and I have lost 74 pounds.
Fat free mass is composed of muscles, body fluid, connective tissue and bones. Apparently the optimal lean to fat ratio for you is 3.2 to 1.
Body Fat: Fat is calories stored as energy reserve for your body. Apprently the desired range of body fat is 18-25% depending on your weight. Anything over that is "excess" which is what you want to get rid of, and by working out and losing weight, you are more likely to gain lean body mass quicker and lose the body fat, doing FAD diets and not getting enough of one thing and too much of another, or by losing weight quickly...you are more likely to lose lean body mass and not as much body fat.
For example, when I was 285 pounds, I had 22% exccess body fat, my goal is 25% body fat, and I had 53% lean body mass, now at 211 pounds I only have 16% body and 59% LBM. Which apparently is excellent!!
I hope this helps!

http://www.3fatchicks.net/img/bar008/slider-scaleblue/lb/285/175/211/.png (http://www.3fatchicks.com/)

06-30-2008, 11:44 PM
The current issue of Prevention magazine quotes that you will lose 70% fat and 30% muscle on an average weight loss plan. Boosting your weight bearing exercise to 3 or more times per will lessen that ratio.

07-01-2008, 12:05 AM
Wow, tons of great info. Thanks! I asked the question in a pretty unintelligible manner. I was trying to ask if my loss of LBM was on the high end or low end of healthy loss. According to CountingDown's response, I am on the way to Glamazonia with only 6% of my loss being lean mass and 94% fat. This month, at least! Hope it keeps up.

Unless I did the math wrong, of course. Then all bets are off.

Thanks again!

07-01-2008, 12:47 AM
You have gotten some good info here, but it seems you lost so little lbm that I do wonder if your stats are right.

But I'm definitely NOT an expert!

What I do know is that it's great you're thinking about this as you're losing and that you're lifting! :strong:

07-01-2008, 08:10 AM
One more thought--you don't mention how your lean body mass was determined. There are a few different types of tests, some less accurate than others. The most accurate test is the hydro test, in which you're immersed in water. The caliper test, performed by a trained individual, can also give good results if the tester is good at it. The electrical resistance testers (hand held, various brands of weighing scales, etc.) aren't as accurate--they can vary from day to day.

Whichever method you had initially, use the same method later to see what the difference is.

The online calculators are the least accurate.


07-01-2008, 10:33 AM
The method is an Omron. I know it's not accurate, but I can't keep myself from playing around with the numbers it gives me.

In terms of actual LBM, I've gained an inch in each thigh and lost inches in the flabbiest spots (belly, upper arms, bust) and I can feel muscles in my legs, arms, and torso that weren't detectable before. Did you know I actually have biceps? That was news to me! I've been lifting every other day and increasing weight each time. I haven't been doing a lot of cardio.

I don't have access to a BodPod or a caliper person, so for now the Omron will have to suffice. I don't take the Omron seriously, really, but I'll take any evidence of progress that I can find. I have a lot of weight to lose -- a long road ahead -- so any little mile marker is motivational, even if it's not 100% accurate. By the time I reach my goal, everything will have changed anyway, so whatever the Omron or the scale or the tape measure says today is just a blip on the screen, as long as the trends are moving in the right direction.

So, yes, I am playing mind games. But it makes the time go faster. And I do appreciate the responses!